Elaine showed her lack of film expertise when she kept trying to 'trap' the studio exec by saying 'isn't that your job, to create movie magic? ' Aren't you supposed to edit and add good music, etc?
She was missing his entire point, which was if the actors have really good chemistry than there are lots of great takes to choose from, and you need less editing and less 'tricks' with music and all that---and there will be that onscreen magic that a director hopes for.
So the exec was saying that although it was possible to fabricate 'chemistry' using lots of edits and film tricks, it is ALWAYS better to have that natural chemistry between the actors to start with.
And I think I know what was left unsaid by the studio exec----Did y'all see that little clip posted here yesterday where it looked like AH was leaning in for a kiss during a photo shoot with Momoa---and he quickly pushed her back and avoided the awkward moment?
That clip made me believe the story that Momoa had complained about the way she was coming on to him and he didn't like working with her under those circumstances. That makes the most sense to me about WHY the studio suddenly considered recasting that role.
Their number one priority is to keep Momoa happy.